Valve is not a company known for getting things out the door quickly, and owners of HTC Vive headsets have been waiting the better part of two years for the company's Knuckles virtual reality input device. Valve's engineers released a development version of the controller called Knuckles EV 1.3 to some of its software partners last summer. Now, the firm is distributing a second revision wearing the Knuckles EV2 moniker to VR software developers. The controller's designers say the ergonomics, strap, sensors, battery life, and support for SteamVR Tracking 2.0 have all improved compared to the last go-round.
The most obvious change is the transition from the thumb-actuated trackpad in version 1.3 to the combination of a thumbstick and a groove-shaped “track button” that can act like a button, a thumb rest, or a semi-two-dimensional trackpad. Valve said developers asked for a thumbstick in droves because of its return-to-center passive force feedback.
The hardware team also put time into making the controllers more comfortable for a wider swath of players, targeting the fifth to 95th percentile of hand sizes. The strap is now adjustable and is made from antimicrobial material.
The “cap sensing” fingertip position detection capability on the grips and triggers of the first developer version of the Knuckles is now supplemented by sensing on all buttons, the thumbstick, and the track button. Developers can access finger position info through SteamVR's Skeletal Input API. Valve says the controller driver parses the sensors' input data into 31 different bone transforms. Interested gerbils can while away their Friday afternoon by reading more about Skeletal Input here.
The force-sensing capability in the Knuckles EV2 is completely new. Force sensors in the grips and the track button can detect light touches or hard squeezes and deliver input to software in digital, analog, or stepped form. Valve says developers should be able to use the new sensors to implement motions like pinching and crushing in VR applications.
Better VR experiences encourage longer playtimes, and the Knuckles EV2 do their part by offering up what Valve calls six-hour battery life. When the pack is depleted, the USB-C port on the bottom of earch controller should make topping them off convenient. Valve says the controllers can recharge at a rate of 900 mA and should go from dead to fully charged in about 90 minutes.
Valve's Moondust tech demo lets developers with EV2 kits play around with the controllers to do things like drive a moon buggy, crush rocks, assemble a space station, and prime and throw grenades. The company says some existing SteamVR games should support the brand-spanking-new controller, but didn't offer any specifics about which ones or which features were likely to work.
Valve made no mention of a possible date for a consumer release of the Knuckles controller in its Knuckles EV2 announcement. The company also didn't provide any pricing details or any information about using the controllers outside of VR applications. Personally, I was most disappointed by the dearth of Sonic the Hedgehog-related puns in Valve's documentation.